ACTH Producing Mediastinal Tumor - Multidisciplinary Approach

Abstract

Abstract Introduction: Ectopic ACTH syndrome is rare but is frequently a severe condition because of the intensity of the hypercortisolism. Patient management is complex and demands both strategies: the diagnosis and treatment of Cushing syndrome, and the specific management of neuroendocrine tumors. Therefore, management should be performed ideally by experienced endocrinology teams in collaboration with surgeons, oncologists, nuclear medicine, specialized hormonal laboratory and modern imaging platforms. Clinical Case: Female patient, born in 2000, at the age of 15 was diagnosed with Cushing’s syndrome secondary to ACTH secretion by mediastinal tumor. At diagnosis, ACTH 1152pg/ml was found (reference value <46pg/ml). Turkish seat resonance was normal, and chest tomography described a 4.5x3.6x3.8cm mediastinal lesion. Underwent a mediastinal surgical approach in 2015, with clinical and laboratory remission of hypercortisolism. The analysis of the lesion revealed a well-differentiated neuroendocrine carcinoma, with Ki67 5%. Progression of the mediastinal lesion was observed, without an exuberant clinic or laboratory, and a new surgery was performed in 2017, with a remaining macroscopic tumor, due to technical difficulties in resection due to contact with vascular structures. The immunohistochemistry of the resected lesion in this approach showed Ki67 30%, which reflects loss of differentiation. Octreoscan was performed, with no uptake. She evolved without exuberant Cushing’s syndrome until May 2019, when the clinical condition decompensated due to hypercortisolism, and was submitted to a new hospitalization. She was assisted by the thoracic surgery and oncology teams. From this moment a follow-up with endocrinology team started. Ketoconazole was introduced and PET-DOTATOC was requested. She underwent chemotherapy with Oxaliplatin and Capecitabine. In March 2020, DOTATOC uptake was checked and a somatostatin analogue was started. She showed considerable clinical and laboratory improvement. The patient remains clinically stable, with control of hypercortisolism using Ketoconazole 600mg daily and Octreotide 30mg every 28 days. The patient remains under clinical and laboratory surveillance. Awaiting PET-FDG. Mediastinal radiotherapy, lutetium, new mediastinal surgical approach, and bilateral adrenalectomy are also considered as possible therapeutic alternatives. Clinical Lesson: The reported case shows a rare location of an ACTH-producing tumor, emphasizing the severity of the presentation, the evolution of tumor de-differentiation, the different results identified in octreoscan and PET-DOTATOC, and the importance of multidisciplinary management.